<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script src="./js/vue.js"></script>
    <div id='app'>
       {{msg}}
    </div>
    
    <script>
        let app =new Vue({
             el:"#app",
             data:{
                msg:'hello world'
             },
             beforeMount() {//挂载之前，模板虽然编译好了，但是还没有挂在到页面上，所以页面无法结合数据展示页面
                console.log("挂载之前");
                console.log(this.$el.innerHTML);
             },
             mounted() {//挂载之后，模板渲染完成，就能看到最终页面
                console.log("挂载之后");
                console.log(this.$el.innerHTML);
             },
        })
    </script>
</body>
</html>